/* IDE4™ Rulebook2 — premium product surface */
:root {
    /* Brand: ink, stone, muted gold — not purple template */
    --color-primary: #6b5a42;
    --color-primary-light: #8a7355;
    --color-primary-dark: #3f3428;
    --color-secondary: #14110e;
    --color-accent: #c4a574;
    --color-accent-soft: #d4b483;

    --color-bg: #ebe6dc;
    --color-bg-alt: #f4f0e8;
    --color-paper: #f7f3ea;
    --color-text: #1a1612;
    --color-text-secondary: #4a433a;
    --color-text-muted: #7a7268;
    --color-border: #cfc6b8;

    --color-success: #3d6b52;
    --color-warning: #a67c2a;
    --color-danger: #8b3a2e;
    --color-info: #3d5a6b;

    --shadow-sm: 0 1px 2px rgba(20, 17, 14, 0.06);
    --shadow-md: 0 6px 16px rgba(20, 17, 14, 0.08);
    --shadow-lg: 0 14px 28px rgba(20, 17, 14, 0.12);

    --radius-sm: 4px;
    --radius-md: 8px;
    --radius-lg: 14px;

    --font-serif: 'Cormorant Garamond', Georgia, 'Times New Roman', serif;
    --font-sans: 'Source Sans 3', 'Segoe UI', sans-serif;
    --font-mono: 'JetBrains Mono', ui-monospace, monospace;

    --sidebar-width: 300px;
    --header-height: 60px;
    --max-width: 1180px;
    --chrome: #12100e;
    --chrome-muted: #9a9288;
}

*, *::before, *::after { box-sizing: border-box; }
html { scroll-behavior: smooth; }

body {
    margin: 0;
    font-family: var(--font-serif);
    font-size: 1.125rem;
    line-height: 1.75;
    color: var(--color-text);
    background:
        radial-gradient(ellipse at 12% 0%, rgba(196, 165, 116, 0.18), transparent 42%),
        radial-gradient(ellipse at 90% 20%, rgba(63, 52, 40, 0.08), transparent 40%),
        linear-gradient(180deg, #e7e1d5 0%, var(--color-bg) 38%, #e3ddd2 100%);
}

.skip-link {
    position: absolute;
    left: -999px;
    top: 0;
    background: var(--color-secondary);
    color: #fff;
    padding: 0.5rem 1rem;
    z-index: 100;
}
.skip-link:focus { left: 0; }

.app-shell { display: flex; }

.shell-main {
    flex: 1;
    min-width: 0;
    margin-left: var(--sidebar-width);
    display: flex;
    flex-direction: column;
}

.main-content {
    flex: 1;
    width: min(100%, var(--max-width));
    margin: 0 auto;
    padding: 1.75rem 1.75rem 3.5rem;
}

.site-header {
    position: sticky;
    top: 0;
    z-index: 30;
    height: var(--header-height);
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 0 1.25rem;
    background: rgba(18, 16, 14, 0.94);
    border-bottom: 1px solid rgba(196, 165, 116, 0.18);
    color: #efeae2;
}

.header-menu {
    display: none;
    appearance: none;
    border: 1px solid rgba(255,255,255,0.15);
    background: transparent;
    color: #efeae2;
    border-radius: var(--radius-sm);
    width: 40px;
    height: 40px;
    font-size: 1.2rem;
    cursor: pointer;
}

.header-search { flex: 1; max-width: 420px; }
.header-search input {
    width: 100%;
    padding: 0.5rem 0.85rem;
    border: 1px solid rgba(255,255,255,0.12);
    border-radius: var(--radius-sm);
    background: rgba(0,0,0,0.28);
    color: #efeae2;
    font-family: var(--font-sans);
    font-size: 0.95rem;
}
.header-search input::placeholder { color: rgba(239, 234, 226, 0.45); }

.header-actions { display: flex; gap: 8px; margin-left: auto; }
.header-btn, .btn {
    appearance: none;
    border: 1px solid rgba(255,255,255,0.16);
    background: transparent;
    color: #efeae2;
    border-radius: var(--radius-sm);
    padding: 0.42rem 0.85rem;
    font-family: var(--font-sans);
    font-size: 0.9rem;
    font-weight: 600;
    text-decoration: none;
    cursor: pointer;
}
.main-content .btn,
.main-content .header-btn {
    border-color: var(--color-border);
    background: var(--color-paper);
    color: var(--color-text);
}
.btn-primary {
    background: var(--color-secondary) !important;
    border-color: var(--color-secondary) !important;
    color: var(--color-accent-soft) !important;
}
.btn-ghost { background: transparent !important; }

.reading-progress {
    position: sticky;
    top: var(--header-height);
    z-index: 25;
    height: 3px;
    background: transparent;
}
.reading-progress::after {
    content: '';
    display: block;
    height: 100%;
    width: var(--read-pct, 0%);
    background: linear-gradient(90deg, var(--color-accent), #8a7355);
    transition: width 0.1s linear;
}

.site-footer {
    padding: 1.5rem;
    text-align: center;
    font-family: var(--font-sans);
    font-size: 0.85rem;
    color: var(--color-text-muted);
    border-top: 1px solid var(--color-border);
}

.sidebar-scrim {
    position: fixed;
    inset: 0;
    background: rgba(20, 17, 14, 0.5);
    z-index: 40;
}

/* Cover */
.cover {
    padding: 1.5rem 0 2rem;
    border-bottom: 1px solid var(--color-border);
    margin-bottom: 2.5rem;
    background:
        linear-gradient(135deg, rgba(20,17,14,0.04), transparent 55%),
        var(--color-paper);
    border-radius: var(--radius-lg);
    padding: 2.5rem 2rem;
    box-shadow: var(--shadow-md);
}
.cover-kicker {
    margin: 0;
    font-family: var(--font-sans);
    font-size: 0.78rem;
    letter-spacing: 0.16em;
    text-transform: uppercase;
    color: var(--color-primary);
    font-weight: 600;
}
.cover-brand {
    margin: 0.35rem 0 0.15rem;
    font-family: var(--font-serif);
    font-size: clamp(4rem, 12vw, 6.5rem);
    line-height: 0.92;
    font-weight: 700;
    letter-spacing: 0.04em;
    color: var(--color-secondary);
}
.cover-tagline {
    margin: 0;
    font-family: var(--font-serif);
    font-size: 1.85rem;
    color: var(--color-primary-dark);
}
.cover-lead {
    margin: 0.85rem 0 0;
    max-width: 28rem;
    font-family: var(--font-sans);
    font-size: 1.05rem;
    color: var(--color-text-secondary);
}
.cover-actions {
    display: flex;
    flex-wrap: wrap;
    gap: 0.65rem;
    margin-top: 1.5rem;
}
.cover-stats {
    list-style: none;
    display: flex;
    gap: 1.75rem;
    margin: 1.75rem 0 0;
    padding: 0;
    font-family: var(--font-sans);
}
.cover-stats li {
    display: flex;
    flex-direction: column;
    gap: 0.15rem;
}
.cover-stats strong {
    font-family: var(--font-serif);
    font-size: 1.75rem;
    color: var(--color-secondary);
}
.cover-stats span {
    font-size: 0.78rem;
    letter-spacing: 0.06em;
    text-transform: uppercase;
    color: var(--color-text-muted);
}

.section-heading {
    margin: 0 0 0.35rem;
    font-family: var(--font-serif);
    font-size: 1.85rem;
    color: var(--color-secondary);
}
.section-lead {
    margin: 0 0 1.25rem;
    font-family: var(--font-sans);
    color: var(--color-text-secondary);
}

.sheet-cards {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
    gap: 0.85rem;
    margin-bottom: 2.75rem;
}
.sheet-cards--wide { margin-top: 0.5rem; }
.sheet-card {
    display: flex;
    flex-direction: column;
    gap: 0.35rem;
    padding: 1.1rem 1.15rem;
    background: var(--color-paper);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-md);
    text-decoration: none;
    color: inherit;
    box-shadow: var(--shadow-sm);
    transition: border-color 0.15s ease, transform 0.15s ease;
}
.sheet-card:hover {
    border-color: var(--color-accent);
    transform: translateY(-2px);
}
.sheet-card-kicker {
    font-family: var(--font-sans);
    font-size: 0.7rem;
    letter-spacing: 0.12em;
    text-transform: uppercase;
    color: var(--color-primary);
    font-weight: 700;
}
.sheet-card-title {
    font-family: var(--font-serif);
    font-size: 1.45rem;
    font-weight: 600;
    color: var(--color-secondary);
}
.sheet-card-lead {
    font-family: var(--font-sans);
    font-size: 0.88rem;
    color: var(--color-text-secondary);
    line-height: 1.4;
}

.archive {
    margin-top: 2.5rem;
    padding: 1rem 1.15rem;
    border: 1px dashed var(--color-border);
    border-radius: var(--radius-md);
    background: rgba(255,255,255,0.25);
}
.archive summary {
    cursor: pointer;
    font-family: var(--font-sans);
    font-weight: 600;
    color: var(--color-text-secondary);
}
.archive summary span { color: var(--color-text-muted); font-weight: 500; }

.service-shell {
    max-width: 40rem;
    margin: 0 auto;
    padding: 0.5rem 0 2rem;
    opacity: 0.92;
}
.service-banner {
    margin: 0 0 1.25rem;
    padding: 0.55rem 0.85rem;
    font-family: var(--font-sans);
    font-size: 0.78rem;
    font-weight: 700;
    letter-spacing: 0.1em;
    text-transform: uppercase;
    color: var(--color-text-muted);
    background: rgba(20, 17, 14, 0.06);
    border: 1px dashed var(--color-border);
    border-radius: var(--radius-sm);
    text-align: center;
}
.service-list { margin-top: 0.5rem; }
.service-back {
    margin-top: 2rem;
    font-family: var(--font-sans);
}
.service-back a {
    color: var(--color-primary-dark);
    text-decoration: none;
}
.page-service .sidebar { display: none; }
.page-service .shell-main { margin-left: 0; }
.page-service .header-menu { display: none; }
.footer-service {
    margin: 0.35rem 0 0;
    font-size: 0.75rem;
}
.footer-service a {
    color: var(--color-text-muted);
    text-decoration: none;
    border-bottom: 1px dotted var(--color-border);
}
.footer-service a:hover { color: var(--color-text-secondary); }

.tier-pill {
    font-family: var(--font-sans);
    font-size: 0.72rem;
    text-transform: uppercase;
    letter-spacing: 0.08em;
    color: var(--color-danger);
}
.tier-pill--module { color: var(--color-primary-dark); }

.modules-block { margin-top: 2.75rem; }
.module-panel {
    margin: 0 0 1.75rem;
    padding: 1.15rem 1.25rem 1.35rem;
    background: var(--color-paper);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-sm);
}
.module-panel-title {
    margin: 0;
    font-family: var(--font-serif);
    font-size: 1.45rem;
    color: var(--color-secondary);
}
.module-panel-count {
    margin: 0.2rem 0 0.85rem;
    font-family: var(--font-sans);
    font-size: 0.8rem;
    letter-spacing: 0.06em;
    text-transform: uppercase;
    color: var(--color-text-muted);
}

.sheet-page {
    background: var(--color-paper);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-lg);
    padding: 1.75rem 1.5rem 2rem;
    box-shadow: var(--shadow-md);
}
.sheet-steps {
    list-style: none;
    margin: 1.25rem 0;
    padding: 0;
}
.sheet-steps li {
    display: grid;
    grid-template-columns: 5.5rem 1fr;
    gap: 0.75rem;
    padding: 0.65rem 0;
    border-bottom: 1px solid var(--color-border);
    font-family: var(--font-sans);
}
.sheet-step-key {
    font-weight: 700;
    color: var(--color-primary-dark);
}
.sheet-step-val { color: var(--color-text-secondary); }
.sheet-page-actions {
    display: flex;
    flex-wrap: wrap;
    gap: 0.65rem;
    margin-top: 1.5rem;
}
.sheet-switch {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
    margin-top: 1.5rem;
}
.sheet-switch a {
    font-family: var(--font-sans);
    font-size: 0.85rem;
    text-decoration: none;
    color: var(--color-text-secondary);
    border: 1px solid var(--color-border);
    border-radius: 999px;
    padding: 0.35rem 0.75rem;
    background: var(--color-paper);
}
.sheet-switch a.is-active {
    background: var(--color-secondary);
    color: var(--color-accent-soft);
    border-color: var(--color-secondary);
}

@media (max-width: 1024px) {
    .shell-main { margin-left: 0; }
    .page-service .shell-main { margin-left: 0; }
    .header-menu { display: inline-flex; align-items: center; justify-content: center; }
    .sidebar {
        transform: translateX(-100%);
        transition: transform 0.28s ease;
        z-index: 50;
    }
    .sidebar.open { transform: translateX(0); }
}

@media (max-width: 768px) {
    .main-content { padding: 1.25rem 1rem 2.5rem; }
    .cover { padding: 1.5rem 1.15rem; }
    .cover-brand { font-size: 3.6rem; }
    .chapter-title { font-size: 2rem !important; }
    .chapter-navigation { flex-direction: column; }
    .sheet-steps li { grid-template-columns: 1fr; gap: 0.2rem; }
}